Many aspects within the construction industry such as structural analysis and production of drawings have been computerized. However quantity surveying work such as measuring the amount of steel reinforcement to be used in reinforced concrete construction, amount of formwork and concrete to be used is still done manually.
Quantity surveying work has to date not been capable of computerization due to the enormous difficulty in reading and interpreting the drawings. The job of the quantity surveyor is a complex one which requires a high degree of skill and experience. Quantity surveyors have to undergo extensive training to acquire the necessary skills.
It is common practice that drawings are drafted using some form of computer aided design format. These drawings are then printed out by quantity surveyors to form an integral part of a tender document for tendering purpose.
In construction projects both developers and contractors spend considerable time and effort to determine the cost of the project. The developer is anxious to ascertain and fix the cost of the project with the contractor and the contractor is anxious to ensure that its tender is realistic, covers all aspects of the construction and that the cost estimate is as accurate as is possible.
In general terms the contractor reviews and analyses the engineering drawings of the project which have been prepared by the developer to determine exactly how much material will be needed to complete the project. At this stage an experienced quantity surveyor has to put in 4 to 5 man months to complete the measurement work of a typical high rise project. Once the total amount of the material has been determined the contractor can then determine the cost per item and hence arrive at the total cost of constructing the project.
The breakdown of materials and costs is set out in a document known as the Bills of Quantity. This document generally runs into several hundred pages. In order to prepare the Bills of Quantity qualified quantity surveyors have to review and analyse all aspects of each and every engineering drawing to evaluate precisely how much material will be required to complete the project as shown in the drawings. The number of drawings which have to be reviewed can number several hundred.
Once the contract has been awarded the developer will usually send its own quantity surveyors to do the measurement all over again to find out whether there are any discrepancies between the measurement records undertaken by the two separate quantity surveying teams. If discrepancies are found the two quantity surveying teams then need to check and rectify the difference as a small percentage of error may mean millions of dollars. The total time spent in measuring and verifying this information may add up to 20 man months and thus is an extremely expensive process.
The analysis of engineering drawings is at present a slow manual process which is very time consuming and very expensive. The task is also very repetitive and tedious and is thus subject to human error.